This invention relates generally to hand tools, and more particularly concerns a combination measuring tape case and gravitational protractor for use in installing tubular conduit and others similar applications.
Tubular electrical conduit is commonly used in construction of new buildings and otherwise to protect electrical wires. Electrical conduit commonly comes in 10 foot semi-rigid lengths in various diameters. Frequently it is necessary to connect two conduit ends together although one end resides at a different level (ceiling) than the other end (floor). In such case, the two ends are connected by a conduit piece, the length of which cannot be readily measured. Heretofore, that piece has been fabricated to length by trial and error guesswork, and likewise, the angle of bend has been the product of trial and error guesswork. This practice can lead to an expensive waste of conduit, when the 10 foot lengths are bent and then cut to fit by the trial and error method. Increased labor time due to the fitting process also is incurred. In complicated installations, the waste can be as great as 20% of all conduit used.
This waste of materials and labor can be virtually eliminated by measuring and calculating the location and approximate angle of the conduit bends. However, heretofore there have been no tools available to the skilled laborer for this purpose or the measurements and/or calculations have been difficult.